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arXiv · 1804.10225

Sigma resonance parameters from a $N_f=2$ lattice QCD simulation

R. Molina·D. Guo·A. Alexandru·M. Mai·M. Döring
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Abstract

In this work we present the analysis of the energy spectrum from a recent two-flavor ($N_f=2$) lattice QCD calculation for pion-pion scattering in the scalar, isoscalar channel (the $\sigma$-meson). The lattice simulation was performed for two quark masses corresponding to a pion mass of 315 MeV and 227 MeV. The $\sigma$-meson parameters are extracted using various parametrizations of the scattering amplitude. The results obtained from a chiral unitary parametrization are extrapolated to the physical point and read $M_\sigma =( 440^{+10}_{-16}(50) - i\,240(20)(25))$ MeV, where the uncertainties in the parentheses denote the stochastic and systematic ones. The behavior of the $\sigma$-meson parameters with increasing pion mass is discussed as well.

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R. Molina, D. Guo, A. Alexandru, M. Mai, M. Döring. 2018-04-26. Sigma resonance parameters from a $N_f=2$ lattice QCD simulation. https://arxiv.org/abs/1804.10225

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